Cold-Related Hazards: Hypothermia and Frostbite

Hypothermia

A medical emergency that occurs when your body loses heat faster than it can produce heat, causing a dangerously low body temperature. Normal body temperature is around 98.6 F (37 C). Hypothermia occurs as your body temperature falls below 95 F (35 C). Prolonged exposure to any environment colder than your body can lead to hypothermia if you aren't dressed appropriately or can't control the conditions.

• Symptoms: shivering, slurred speech or mumbling, slow shallow breathing, weak pulse, clumsiness or lack of coordination, drowsiness or very low energy, confusion or memory loss, loss of consciousness, bright red, cold skin (in infants)
• Treatment: methods to warm the body back to a normal temperature.
  • Be gentle. Limit movements to only those that are necessary. Don't massage or rub the person. Excessive, vigorous or jarring movements may trigger cardiac arrest.
  • Move the person to a warm, dry location if possible.
    • Keep him or her in a horizontal position if possible.
  • Insulate the person's body from the cold ground.
  • Remove wet clothing. Cut away clothing if necessary to avoid excessive movement.
  • Cover the person with layers of dry blankets. Cover the person's head, leaving only the face exposed.
    • Do not apply direct heat. Do not use hot water, a heating pad or a heating lamp to warm the person. The extreme heat can damage the skin or, even worse, cause irregular heartbeats so severe that they can cause the heart to stop.
    • Use a first-aid warm compress (a plastic fluid-filled bag that warms up when squeezed) or a makeshift compress of warm water in a plastic bottle or a dryer-warmed towel. Apply a compress only to the neck, chest wall or groin.
    • Do not apply a warm compress to the arms or legs. Heat applied to the arms and legs forces cold blood back toward the heart, lungs and brain, causing the core body temperature to drop. This can be fatal.
  • Monitor breathing. A person with severe hypothermia may appear unconscious, with no apparent signs of a pulse or breathing. If the person's breathing has stopped or appears dangerously low or shallow, begin CPR immediately if you're trained.
  • If the affected person is alert and able to swallow, provide a warm, sweet, nonalcoholic, non-caffeinated beverage to help warm the body.

Frostbite

Frostbite is an injury caused by freezing of the skin and underlying tissues. First your skin becomes very cold and red, then numb, hard and pale. Frostbite is most common on the fingers, toes, nose, ears, cheeks and chin. The most common cause of frostbite is exposure to cold-weather conditions. But it can also be caused by direct contact with ice, frozen metal or very cold liquids. Exposed skin in cold, windy weather is most vulnerable to frostbite. But frostbite can occur on skin covered by gloves or other clothing. Possible complications of severe frostbite include infection and nerve damage.

Stages of frostbite:

Frostnip. Frostnip is a mild form of frostbite. Continued exposure leads to numbness in the affected area. As your skin warms, you may feel pain and tingling. Frostnip doesn't permanently damage the skin. You can treat frostnip with first-aid measures, including rewarming the affected skin. All other frostbite requires medical attention because it can damage skin, tissues, muscle and bones.

Superficial frostbite. Superficial frostbite appears as reddened skin that turns white or pale. Your skin may begin to feel warm—a sign of serious skin involvement. If you treat frostbite with rewarming at this stage, the surface of your skin may appear mottled. And you may notice stinging, burning and swelling. A fluid-filled blister may appear 12 to 36 hours after rewarming the skin.

Deep (severe) frostbite. As frostbite progresses, it affects all layers of the skin, including the tissues that lie below. Your skin turns white or bluish gray, and you may experience numbness, losing all sensation of cold, pain or discomfort in the affected area. Joints or muscles may no longer work. Large blisters form 24 to 48 hours after rewarming. Afterward, the area turns black and hard as the tissue dies.

• Symptoms: At first, cold skin and a prickling feeling, numbness, red, white, bluish-white or grayish-yellow skin, hard or waxy-looking skin, clumsiness due to joint and muscle stiffness. In severe cases, blistering after rewarming.
• Treatment: While you wait for your emergency medical help or a doctor's appointment, take appropriate self-care measures, such as: protecting the affected area from further cold, not walking on frostbitten feet, reducing pain with ibuprofen (Advil, Motrin IB and others).